Vertical sand damper



Z w F W. S. MAYERS VERTICAL SAND DAMPER Filed Oct. 29, 1937 May 14,1940.

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Patented May 14, 1940 UNITED STATES PATENT OFFICE 1 Claim.

This invention relates to dampersor valves for shutting off andre-establishing the current of hot gas in the mains and branches ofconduits leading from gas producers to the various combustionchambers,or hot gases from combustion chambers, and is designed to be used inhorizontal pipes or conduits.

The invention embraces an improvement in the construction of the sanddampers described and shown in Letters Patent No. 1,663,915 issued to meon March 27, 1928, to which reference is made.

In the practical use of these sand dampers it occurs that the closureplate in contact with the hot gas sometimes adheres to its seat (life tothe formation of a burned tar deposit between the seat and the plate sothat it is difficult or impossible to raise the plate without firstjarring it loose.

To overcome this difiiculty my object is to provide means for insertinga pointed bar under the edges of both plates by which they may be jarredloose and the tar seal broken.

A further object of the invention resides in the use of double doorshinged at their adjacent ends near the vertical center line of the castiron body. The section of the iron rim at this point and the extra wideconnecting flanges, all integral parts of the main castings, providestrong tie members for resisting the mechanical strains caused by thesagging of the heavy conduits which are thereto attached. With a singledoor having a length equivalent to that of the two doors it is evidentthat the parts would have considerably less strength in resisting thestrains due to sagging at the point where strength is most needed.Furthermore the double doors permit the casting of the body in twosections, the joint being in the vertical axial centerplane as shown. Asall parts of the sand damper body on one side of the verticalcenterplane are symmetrical with such parts on the other side it isnecessary to construct only a half pattern, thus reducing the cost ofmanufacture.

The drawing shows the body split also on the horizontal axialcenterplane. This is recommended only for the large sizes which arefitted to conduits of from six to ten feet in diameter.

Referring to the drawing, Fig. 1 is a section through the radialcenterplane II in Fig. 2; Fig. 2 is a section through the vertical axialcenterplane 2-2 in Fig. 1; Fig. 3 is an enlarged section on the line 3-3in Fig. 1 and Fig. 4 is a perspective view of the loose cover plateforming the top closure after the damper plates are withdrawn. I

The sand damper is shown in its complete form comprising the cast ironbody I as a unit in quarter sections, the hoist frame 2, the plates 3,4, the winch '5, the sheaves 6, I, 8, 9, the cable Ill, II, thecounterweight I2 and the loose cover plate I3.

The seats Ia, lb are offset in sections as shown so that a pointed barI4, indicated by dotted lines in Fig. 3, may be inserted for prying theplate loose from its seat. The bar may also be used for this purposethrough the poke holes I5 after the plugs I6 are removed and alsothrough the channels I1, I8 from above.

In Fig. 1 the damper is shown with the plates hoisted to the openposition and resting upon a loose piece of steel channel I9 which isplaced upon the curbs I c, I d of the enlarged top of the damper body.In order to stabilize the plates while thus supported, with the hoistingcable II slack, the holding angles 20, 2| are attached to the main frameangles through the gusset plates 22, 23. Attached to the gusset platesare the short angle guides 24, 25, the inwardly extending legs being cutas shown to facilitate the entry of the plates between them.

For stabilizing the plates in the crosswise direction the steel bars 25,21 are inserted in holes through the main angle supports and gussetplates.

With the damper open, as in Fig. 1, the loose cover plate I3 is placedin the enlarged top of the body casting and covered with sand to a depthof a few inches.

When it is desired to close the damper the plates are first hoisted bythe winch 5 to their topmost position which is followed by the removalof the sand cover and the channel I9 and cover plate I 3. The plates arethen lowered to their closed position within the body and the spacebetween them and the enlarged top filled with sand.

The damper plates are connected together at their tops only through theinverted U shape yoke 28 which has suflicient resiliency to permit themto be sprung inwardly a short distance from their seats for the purposeabove described.

The doors 29, 30' are hinged at their adjacent ends near the center ofthe damper body so that when open they are held back to back by gravityin which position they do not impede the digging out of the sand seal.They are held when closed by the threaded nuts on the swing bolts 3|,32.

A multiplicity of holes, not shown, extend around the rims le, If atequal spacing for receiving bolts or rivets which bind the shells of theconduits to the rims in a well known manner.

When the conduit is to have a refractory lining, which it usually has,the brick or blocks may abut the seat flanges la, lb and in preferableconstruction the inside diameter of these flanges is somewhat less thanthe inside diameter of the refractory lining in order that the edges ofthe flanges may be protected from direct contact with the hot gases.

When the plates 3, 4 are lowered into their closed position a close fitagainst their respective seats is not essential since the seal iseffected by the sand diaphragm which completely fills the space betweenthe plates as well as the enlarged portion at the top of the damperbody. Being somewhat moist when placed in the damper the sand will notrun through narrow interstices between the plates and their seats andthe webs of sand which are exposed to the hot gas soon become set, dueto the tar which is suspended in small particles in the gas.

I claim:

In a sand damper, a casing having opposed spaced sides, and providedwith a plurality of spaced openings, each side formed with anuninterrupted integral seat, which extends inwardly in the space betweenthe sides, a slide composed of spaced plates engageable with therespective seats, and means to resiliently connect the plates so thatsame can freely move inwardly of the casing, said plates extendingoutwardly beyond the outer terminals of the seats throughout thecircumference of the latter and the seats being of such width as to holdthe plates of the slide at such predetermined spaced distance from theinner faces of the sides of the casing as to provide for the insertionof a prying tool of a size so as to enable the plates to be pried out ofengagement with the seats, and the bounding edges of the plates beinglocated in such relation to the bounding edges of the sides of thecasing, whereby such latter edges provide a fulcrum for the prying tool,the openings of the casing being located at the top and bottom and onopposite sides thereof, whereby the plates may be pried away from theirrespective seats throughout substantially the circumferences of theplates.

WILBUR S. MAYERS.

